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U.S. ZIP Codes Database 2026

Search by ZIP code, city, county, or state and find clear postal details with maps, time zones, and area code data.

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Gregory County ZIP Codes

Browse all ZIP Codes, cities, and associated area codes registered in Gregory County.

County State ZIP Code City Area Codes
Gregory County SD 57317 Bonesteel 402, 531, 605
Gregory County SD 57335 Fairfax 402, 531, 605
Gregory County SD 57523 Burke 402, 531, 605
Gregory County SD 57529 Dallas 402, 531, 605
Gregory County SD 57533 Gregory 402, 531, 605
Gregory County SD 57538 Herrick 402, 531, 605
Gregory County SD 57571 Saint Charles 402, 531, 605

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About U.S. ZIP Codes

ZIP codes are a United States Postal Service system introduced in 1963 to make mail routing more accurate and efficient. The standard format uses five digits, while ZIP+4 adds four more digits for a more precise delivery segment.

ZIP codes cover the United States, its territories, military mail routes, and other USPS delivery points. This directory organizes that data for practical lookup by ZIP code, city, county, and state.